Calibration
by The Divine Comedian
Summary: Remus's mind is usually a tidy place. The worst has already happened, what's left to be scared of? His fears are labelled, annotated, and most of all, archived. For one evening, though, he'll have to let them come out and play. (Remus trains the Boggart for his lesson with the third years. Featuring Severus Snape as an unwanted critic, and Sirius Black as the elephant in the room.)


I was wondering belatedly about that Boggart lesson in PoA. It seems quite intrusive on the children's minds. Knowing Remus, his lesson prepration must have taken that into account.

 **Note** : contains mentions of child abuse and some disturbing/violent imagery.

* * *

 **Calibration**

* * *

The Boggart is old, and weary, and out of practice, after so many years stuck in that cabinet with only pests for company. What are woodworms scared of? Remus wonders. Cellar spiders? Ladybugs? The Boggart is currently neither. In fact, it's hard to say _what_ it is.

Remus watches the shapeless blob spinning slowly in mid-air, expanding this way and that, as if pushing against imaginary boundaries. Up until now, Remus has worried a Boggart might be too much for the third years. In all honesty, though, this one might be too boring.

His new office has a window, which is all the more remarkable because, so far, Remus hasn't even had an office. He turns his back on the sad, indecisive mass still rotating in the middle of the room. Thinking, thinking.

Lesson one for tomorrow: _Don't turn your back on the Boggart_. Corollary to lesson one: _Unless, of course, you know exactly what you're doing_. Unbeknownst to it, the Boggart is reflected in the window, competing for attention with the dusky outside.

Remus is not in a contemplative mood. Unfortunately, to prepare his lesson for tomorrow, he has to be. He forces his mind to wander. The future, the past. Hogwarts is so full of both.

One fact about the future: Tomorrow he will teach his dead friend's son for the first time, and he needs to get it right. One fact about the past: The desk in his office, where he drew up his lesson plan, happens to be the exact same desk he once spent four hours sitting at in detention: _I will not let Sirius Black free the Cornish pixies during a ministry inspection again_. How oddly specific, come to think of it. Full of loopholes.

Welcome to Hogwarts.

There's movement in the reflection. "All right," he says. "You had a good, long look. What have you got for me?"

He turns towards the Boggart. In the middle of the room, there stands a hooded skeleton, faint blue light bouncing off the sharpened edge of its scythe, bones rattling like a ghostly xylophone, robes flapping in a non-existent wind. Could be worse, Remus thinks. At least the old Boggart got the genre right.

"Ah, death," Remus says. "Good presentation. Nice visuals in particular. Not altogether very original, though."

The skeleton lowers its head sadly. Disappointed at the less-than-panicked response? Hard to tell what a Boggart is thinking. And it may be a weak old Boggart, but it's primarily a hungry Boggart, and Boggarts feed off fear.

It'll have to try harder, then.

Remus's mind is usually a tidy place. The worst has already happened, what's left to be scared of? His fears are labelled, annotated, and most of all, archived.

For one evening, though, he'll have to let them come out and play.

"Try again," he says. "It's all there, you have to learn how to look for it – "

The Boggart changes into another sad figure. Again, impressive visuals: the sightless eyes, slack mouth, jerky movements, like a marionette -

"Really, an Inferius?" Remus sighs. "I don't fear them, I pity them. You're telepathic, note the difference. And here's another tip: You'll want to be a bit more personal. There's no one-size fits all with fear."

That imprint of a departed soul in front of him starts shifting and twisting, with more purpose than before, occasionally settling for a shape, testing its impact on Remus. It's no good, though, the Boggart is just changing through a handful of generic representations. It is like watching a particularly bad Muggle horror movie.

Some of them seem dated; things that might have worked for the Boggart back in the 1940s: A stern-looking Muggle doctor, a tall handsome wizard that can only be Gellert Grindelwald, a German Wehrmacht soldier.

Remus laughs. "Why not Hitler, while you're at it," he says.

The Boggart obliges for a split second. Then, realising what just happened, it turns back into an offended blob. Projecting an air of disappointment, Remus turns back towards the window.

Outside in the dusk, the Whomping Willow is swaying in the brisk autumn wind. She's losing her leaves. He remembers how that always made her more irritable – to the roots, in fact. Autumns always meant a rough passage to the Shrieking Shack.

That bloody tree. He had been sure they would have cut it down by now. He hadn't expected they'd ever accept another werewolf, and who could have blamed them, after –

But then, this werewolf hadn't particularly wanted to return, either.

"Well, well, well," says a raspy voice behind him. "What do we have here?"

Remus _almost_ jumps. Instead, he turns slowly, facing Fenrir Greyback. The man is improbably tall, though, towering over Remus, as if Remus were five years old again. Even the room appears changed – it is the same stuffy office, but with a note of leafy green darkness. It smells of musk and then of blood.

Wonderful craftsmanship. Remus raises an eyebrow in appreciation. "Oh, we're getting warmer," he says. "Good old childhood days, when fears had a face and a name."

"I remember it well," says Greyback. "You were so, so scared."

"I know, right?" Remus says quietly, speaking to the Boggart, not Greyback. "Easy pickings for you. Maybe too easy. Take some pride in your work, will you?"

"There you were, alone in the woods, and why? Wrong place, wrong time, my lad. It's just the law of nature."

"Wrong," Remus says. "Greyback had stalked me since the new moon. He planned this. And the reason I was alone in the woods was because he dragged me there."

He smiles. "Good effort, though. Bravo. Just when I thought I had finally forgotten the smell."

Does the Boggart know that is a lie? If it does, then the whole evening is probably wasted. Unexpectedly, however, Greyback smiles back. "Remus Lupin," he says. "What a name." He had said much the same at the time.

"I know," Remus says. "Coincidence of the century." He doesn't like this much. The Boggart is too confident. Remus's hand is, just so, resting on the wand hidden in his coat pocket. If need be, he'll go for the teeth, he decides. Greyback without teeth will be sufficiently silly.

Greyback mauled to death by a werewolf would be overkill.

Probably.

"Only it wasn't a coincidence, was it?" Remus says calmly. "My mother loved Roman mythology. Greyback was not one for subtlety, and this was probably his idea of poetry. He couldn't resist me after he learned my name. My mother drank herself to death," he adds. "You could turn into her next."

"But you forget," says the Boggart with Greyback's savage mouth. "I'm still alive. I come back for you. Take what's left."

There's an instinctive response to this threat, lurking in the underwood of Remus's mind, but he passes over it. Instead, he makes himself laugh. "No," he says. "Greyback likes them young. I'm quite safe from him. _Try harder_."

Despite his words, he lets some of the old fear escape, like opening a valve to relieve pressure. He needs to feed the Boggart: It's so old, and so weak, and so hungry. But Greyback just stands there, dejected, and that looks so comical that Remus is laughing for real now.

"Really," he mocks the Boggart. "Is that the best you can do? You've had all evening, and I'm really expecting more from – _oh hell no_."

Yes, that is a proper startle, and worse, the Boggart registers it. For the first time, Remus is seriously reconsidering tomorrow's lesson plan. Standing in the middle of his office are James and Lily Potter, quite obviously dead, holding their one-year old son Harry, quite obviously terrified.

And apart from everything else that's wrong with it, this is probably _not_ an image to parade in front of the third-year Gryffindors tomorrow.

It is crucial to remain calm now. He draws a deep breath.

"Aren't you getting a wee bit confused?" he says. "You're a Boggart, not a Dementor. These are my friends, I'm not scared of them. I mourn them. As a creature whose entire purpose is to scare people, you should know the difference."

He closes his eyes, just to give his brain a temporary respite from the sight in front of him. There's no fun in mocking the Boggart, even if that is the only language it understands. He tightens his grip on his wand. But he can't come up with a way to make the tragedy in front of him look ridiculous. _It's just makeup, for Halloween_ , he thinks. That terrible Halloween, and no, it isn't.

Best to distract it, then. Remus concentrates on something, anything else, the first scary thought that comes up, and opens his eyes.

"Ah," he says. "I see we're back to the Werewolf theme."

In front of him stands a teenage Severus Snape, dead, and torn up. Bits of him are missing. It does nothing to improve his looks.

"Good job," Remus says conversationally. "Love the detail on the intestines. That _was_ quite scary at the time, you know. My best friend pulled a prank that night that might have left one kid dead and another a murderer. Some prank, I know. But since you are already in my memories, know this: It didn't happen, and furthermore, it didn't happen _seventeen years ago_."

Dead Snape is probably a step up from the previous image, but still not entirely suitable for the classroom, he decides. Slightly more gore than he expects the average thirteen-year-old to handle.

"And you know what?" he adds. "It didn't matter. He succeeded just a few years later. Three of my friends are dead, and the fourth is a murderer. You keep returning to the past, but I'm not scared of it. It's over. It can't hurt me."

He expects the Boggart to follow his guidance on this one, too, but the Boggart is getting full of himself. It has realised what nerves are worth striking. The image becomes even stronger.

"Listen to me," Remus says. "Have you forgot how to be a Boggart? Look in the future, not the past. You want to scare me? Pick something that might still happen."

There is no change, apart from dead Snape looking a bit smugger than he has any right to be.

"You don't believe me, do you?" Remus says. "You plucked that image straight out of my brain, you tell me if I'm lying. You tell me if I'm scared of it."

Still no change.

"All right," Remus says. "You snatched up a random scary image from my brain, but you didn't stick around to learn what it was about. Let me tell you."

Remus pauses. He really, truly, doesn't want to do this. But as a responsible teacher, he needs to know how far this Boggart will go. What it will do with an actual, ongoing fear. And how to handle it then.

"When Sirius went to Azkaban for what he did," Remus starts again, "I moved heaven and hell to get a visitor's permit. I didn't want to see him, I just wanted to ask _why_. Why he destroyed the best thing that ever happened to any of us, and why he laughed doing it. I wanted to know what was _so bloody funny_."

Dead Snape is listening curiously.

"It took two months to get the bloody permit," Remus says. "I swear, the easiest way to get into Azkaban is to murder someone. So many hoops to jump through if you just want to visit. Nearly failed the background check. They thought I'd try and break him out. _I_ thought I might, if he gave me a good enough reason. Night before I meant to go, I dreamt of _this_ –"

He waves in the general direction of the Boggart.

"And I realised I already knew what was so bloody funny. It's because _this_ is his idea of a joke. James and Lily dead in a grave. Peter blasted to smithereens. Little Harry an orphan with his terrible relatives. Sirius showed his face in our fifth year, and he talked and talked and made me forgive him, but he never truly changed. And I didn't want to listen to him anymore."

He decides to spell it out for the Boggart. "And I was scared," he says. " _I am scared_ – that I was wrong. That I should have gone and listened to what he had to say."

Another transformation. Remus has barely time to look out of the window and back.

"You should have listened," Sirius says.

He looks good, so much better than the photo the _Prophet_ keeps printing. It's what teen heartthrob Sirius might have grown into if he hadn't been a murderous lunatic. His bright eyes are wide open and sincere.

"You never thought it was me, didn't you?" Sirius says. "I was never very well-adjusted, but loved that man. You know I did. There was so much darkness in me, but he saved me. And you. And – _him_."

"Yes, I remember," Remus says. "I remember that day."

"Then you remember me at my worst," Sirius says. "But remember this, too. I was your friend when you had no-one. I spent four years learning to become an Animagus to keep you company. Four years, just to spend one more night a month with you. I fought against the Death Eaters by your side. And after all these years, do I not deserve to speak up for myself? Do I not deserve the benefit of the doubt?"

"After all these years that you threw away?" Remus says. "Let me tell you what you gave up. You could be a free man today. Have your own family. A pint with James on Saturdays. Little Harry could be with his parents. You'd teach him all sorts of nonsense when Lily isn't looking. Peter – Peter could have grown into himself. Did you ever wonder what he could be today?"

"Peter would never have amounted to anything and you know it," Sirius says dismissively. "Remember how James was? He was a good man, but boy, he loved the attention. Even that sad little sycophant would do."

"Peter was worth a thousand of you," snaps Remus. "He came after you. He faced you."

Sirius smiles thinly. "I notice _you_ didn't."

There's probably a point in there, but belatedly, Remus catches up with himself. He is not talking to Sirius. It's just a Boggart. Just a creature whose entire point is to be as terrible as possible.

" _You_ could have taken me on," Sirius continues. "Even better, you could have made me listen. You didn't even try."

 _I was scared_ , is what Remus almost blurts out. This is exactly why he had always avoided arguments with Sirius, and the Boggart is making a good effort to emulate him.

"Because I couldn't predict what Sirius would do," he says. "Because I couldn't predict what _I_ would do. I'd rather be a coward than a murderer."

"Some Gryffindor," Sirius says with a shrug, and there it is again, that mad glint in his eyes. It was there before Azkaban. "This is why you hide in a castle, now that I am about and about?"

 _Yes_. "No," Remus says.

"Still scared to know the whole truth, then," Sirius says.

It's just the Boggart, Remus reminds himself again. All it knows comes from Remus's memories, and this whole supposed truth it dangles in front of him, it isn't – it can't be – anything new, anything he doesn't already know, anything he hasn't pondered to death during so many sleepless nights.

"I believe I know enough," Remus says.

"The Remus I remember wouldn't even pick a favourite bubblegum flavour without researching the history of food additives," Sirius says dismissively. "That's one thing I adored in you: You _never_ thought you knew enough. What happened?"

It should be obvious, thinks Remus, even to a creature of such limited compassion.

"You," he says.

The Boggart, with Sirius's face, smiles warmly. "Remember the days we had, Remus. Remember how clever I was. Of course I noticed you didn't come after me. I noticed you didn't visit. I know you're still doubting. And that's why I'll come for you. Just, when I do – remember the days."

"I remember them well," Remus says. " _You_ didn't. Don't expect help from me. Don't come here at all. You know what's waiting for you here, do you?"

He waves towards the window. In the distance, Dementors are circling the grounds, dark outlines against the indigo sky. Something has stirred them tonight. They're looking for one man in particular, and when they find him, may God have mercy on his soul. Because they won't.

"I don't deserve this," Sirius says.

" _You chose this_ ," Remus says. "Over your humanity. Over your integrity. Over your _friends_."

Sirius shrugs, his attention oddly drawn to the Dementors in the dark. "I notice you haven't made any new ones."

"No," Remus says. "I knew better than that."

"All for the best," Sirius says. "You know they wouldn't have measured up to us. Remember the day I took a bludger to the solar plexus because James was too busy showing off to see it coming? That was in third year. That was when I realised I'd die for him."

"I wish you had," Remus says.

"I wish I had," Sirius says simply. "You're right. It's been no life at all. For none of us. I'm _sorry_."

It sounds sincere. Worse, it sounds like _Sirius_. Remus knows an expert manipulator when he sees one, and this one has just shown his cards.

"Enough," Remus says. "I wish I could forgive him. But you know what? He never apologised. He never will. And you're. Not. Him."

He draws himself up. "I'm talking to my own worst fear," he says, "and it talks back. It doesn't change the facts. He isn't innocent. There hasn't been a terrible mistake. And yes, he might come for me, but I am prepared."

He realises belatedly why that Boggart had been locked up in a cabinet for fifty years. It's old, yes, and weary, that too, but it is also clever and sly and _hungry_. And Remus has just given it all it wanted.

He thought he was training it. Now it's training _him_.

Well then. Defence against the Dark Arts isn't _just_ about the mind games.

He leans into the ghostly Sirius, stares him down. "You show that face tomorrow," he says, "or ever, and I'll make sure you'll never leave that cabinet again. You play nice, you'll get a bunch of thirteen-year-olds to startle. Yes, the fear will be snack sized, but there's going to be a lot of it. What do you say?"

There is a wicked smile on Sirius's face, one that Remus is sorry to say doesn't actually look out of place, and the Boggart turns back into dead Snape.

"No, not that one, either," Remus says.

Lily and James.

"Nope."

Greyback.

Remus sighs. "Okay, an easy rule that even you will understand: No person, living or dead. Or it's the cabinet for you, and I'll seal it myself."

Greyback gives a shrug, and his shape collapses into thin air with a pop. It re-emerges as a small silvery orb.

Moony smiles. Now that's what he has been talking about. Personal, accurate, and it would take an exceptionally smart student to figure this out.

"Oh, my old friend," he says. "You are quite right. I never look forward to it. But you know who wasn't scared of what the werewolf would do? Sirius wasn't. A little fear keeps you careful. Just never let it do the talking."

Remus leaves the orb hanging around in the middle of the office for now, just to make sure the Boggart will be sated and manageable tomorrow.

He's busy preparing an elaborate cup of tea when there's a brisk knock on the door.

Of course. The full moon is in two days, and the Boggart is not the only one who has picked up on it.

"Come in," he says without looking. "Cup of tea? Kettle's just boiled."

"The moon?" says an unpleasant voice, and Severus Snape emerges from the shadows, a smoking goblet in his hands. "How have you not, after all these years, become used to it?"

Of course Snape would recognise a Boggart at once, even one as oddly shaped as this one. Remus has forgotten how _smart_ this man is. How perceptive.

"I'm still calibrating," Remus says. He turns, accepting the Wolfsbane potion from Snape with a courteous smile. It smells horrible.

"Pity," Snape says. "I was keen to know what monsters were scared of."

"Other monsters, of course," Remus says. His teenage years have left him with an acute sense of how to get under Severus Snape's skin, and ignoring the man's insults is one of them.

"There's no good reason to 'calibrate' a Boggart," sneers Snape, trying a different angle. "Surprise is part of the charm."

Of course Snape would be a fan of Boggarts. Remus feels it's going to be a long year.

At the sound of Snape's voice, the Boggart has turned its attention towards him. There is some added tension in the room as it's scanning Snape – so much gloom in that man, Remus thinks. He has got to admit he is a bit curious.

But the Boggart spins and flickers without settling on a form. Snape, the Occlumens, watches it, a thin smile of superiority on his sallow face.

Remus takes this moment to banish the Boggart with a flick of his wand. The cabinet doors snap shut, and he puts a silencing spell on it for good measure. Can't have it listening in. That thing is way too clever.

"There is one good reason," Remus says. "A Boggart can't help its nature. It is fundamentally cruel."

"And?"

"And I'm going to set it on the third years."

There is a pause in which Snape ponders the locked cabinet, which is rattling in silence. "I can't say I see anything wrong with that," he says.

Oh lord, grant him patience.

"Some thirteen year olds are scared of spiders, or birds," Remus says, in the tone he used to talk James and Sirius out of their more insane ideas. "Other thirteen year olds are scared of far, far worse things. I'm not having this thing turn into someone's bully, or a dying parent, or a child molester." He pauses. "Not to give you ideas for when you eventually do get my job."

Snape doesn't react to that last part. "Or the Dark Lord?"

"Or that, yes." Remus makes a mental note that he really has to do something about Harry Potter. That fear, he imagines, must shine bright and pure. No calibration in the world is going to make that Boggart ignore it.

"How did you do it?" asks Snape. He sounds intrigued, despite himself. Well, Remus is not going to just ignore an attempt at normal conversation.

"I let it try out a few different forms," he says. "I rewarded what I thought was classroom-appropriate, and I mocked what I thought wasn't." At least, that had been the idea. "Oddly, it seems to have picked up a slight tendency for metaphors."

"Rewarded it with –"

"Fear, yes," Remus says. "We have far more control over our emotions than we think."

Unless, as it turns out, when it comes to Sirius Black.

"But you would know all about that," he adds. "How would you have done it?"

"I wouldn't, of course," Snape says dismissively. "The children will encounter Dark Magic in their lives, and it is not going to be, how did you phrase it, _classroom-appropriate_."

"Children don't generally learn well when they're paralysed with fear," Remus says.

"Not all of them, no," Snape says. He regards Remus for a moment. "You're taking this whole teaching thing more _seriously_ than I thought you would," he says.

"I take everything seriously," Remus says, again glossing over the provocation. For now. "Why did you not expect this?"

"I rather thought," Snape says, "that you are here because this is where Black is going to go."

Remus takes a politely puzzled sip of what turns out to be the potion, grimaces, then swaps it out for his tea. "I am here because Albus asked me to," he says.

"And did he ask you before or after Black escaped?"

Remus has a feeling he knows where this is going. "After," he states calmly. "I might have been asked to keep an eye on the boy… but that's no secret, isn't it? I'm sure Albus told you."

"Funny," Snape says, in that low, menacing tone. "I rather thought that you are here so Albus could keep an eye on _you_."

"Did you." Remus closes his eyes just for one moment. Of all the people to not have killed in his fifth year, could it have been _anybody else_?

"Thank you for the potion, Severus," he says. "I appreciate it. I'm sure you had a long day."

"Indeed I had. I'll best leave you to your… lesson planning," Snape says with all the politeness the man is capable of.

Just testing the waters, then.

Well.

When Snape has left the premises, Remus breathes a sigh of relief. He briefly lifts the silencing charm off the cabinet, knocks on it three times, and says: "Remember what I said about not turning into real people?"

He glances towards the door, but Snape has long since stalked off.

He still whispers conspiratorially. "Feel free to turn into Snape any time you like," he says. "I could use a laugh."

* * *

 _The end._


End file.
